Idrijska Bela, Belčne klavže

Klavže or klavža barrages are unusual technical devices which were used for floating timber downstream to the mine in Idrija along the Idrijca, Belca and Zala from the 17th until the 19th century. Several well and less preserved klavže barrages (Idrijske, Putrihove, Smrečne) are hidden in the hinterland behind the Lake Divje Jezero. The klavže barrages at the Belca Stram are entirely renovated. According to the local Jožef Mrak, the riverbed was dammed with a stone barrier protected by a wooden overhang. In it is a vaulted opening that was closed by wooden gates. The klavže were built around 1770.

According to calculations, there is up to 210,000 m3 of water in the artificial lake behind the dam. With a quick opening of the klavže, water was released into the riverbed, where logs had been placed and were floated downstream to the grablje or rake, a barrier dam made from stakes sunk into the water in front of the town of Idrija.